Haltech F9A - Manual (Page 68)

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If the engine will not idle when cold but will when the engine is warm then the coolant
correction map needs to be adjusted.
If you are not using an idle air control motor then adjust the idle using the idle adjust screw
on the throttle body. Check for any air leaks in the manifold.
If the engine surges or hunts at idle then the mixtures and timing are wrong. Readjust the fuel
maps near idle conditions.
In some circumstances it may be necessary to use the Zero Throttle Map. Consult Chapter 6
[6.2] for information on using the Zero Throttle Map.
A.5 Light throttle and Cruising Problems
If the engine falters under light load then the mixtures might be too lean, check the Fuel
Maps.
A.6 Full Power Problems
If the engine gasps under full throttle then the mixture may be too lean. If the engine bogs
down and blows smoke then the mixture is rich. Re-check the fuel maps
If the maps appear to be correct then ensure that the fuel pressure is not falling out of
regulation by using a fuel pressure gauge. Flow test and clean the fuel injectors
In some circumstances it may be necessary to use the Full Throttle Map. Consult Chapter 6
[6.3] for information on using the Full Throttle Map.
A.7 Throttle Response
Throttle response of the F9 is set using the three pairs of throttle pump settings. If the engine
gasps and flat spots (misfires) when the throttle is suddenly opened then the throttle setting is
not high enough or is much too high. If the engine bogs down but continues to run then the
mixture is too rich. Experiment with the throttle pump settings to achieve the optimum.
The throttle pump coolant factor affects the throttle pump only when coolant correction is
being applied, i.e. before the engine has reached operating temperature. Set the throttle pump
increase and sustain figures only when the engine is warm. Wait until the engine is cold
again, and the coolant correction map has been set for good stable running, before changing
the coolant factor.